U 2004/11/17 14:59:59.255342 68.80.200.100:1063 -> 68.80.201.101:5060 ACK sip:4075551212@216.229.127.60:5060 SIP/2.0. Via: SIP/2.0/UDP 192.168.0.83;branch=z9hG4bKe15e695c98bd9cb0. Route: sip:68.80.201.101;ftag=4edd147cdac0025f;lr=on. Route: sip:216.229.127.60:5060;lr. From: "Paul (1002)" sip:9990010001@sip.mycompany.com;user=phone;tag=4edd147cdac0025f. To: sip:14075551212@sip.mycompany.com;user=phone;tag=0bf5212d. Contact: sip:9990010001@192.168.0.83;user=phone. Proxy-Authorization: DIGEST username="9990010001", realm="sip.mycompany.com", algorithm=MD5, uri="sip:4075551212@216.229.127.60:5060", nonce="419baee2139477c22db6d0ec9a47b23003512431", response="7b83435f78bc60f5ced80304c7d54093". Call-ID: aa31202374f54793@192.168.0.83. CSeq: 12010 ACK. User-Agent: Grandstream BT100 1.0.5.11. Max-Forwards: 70. Allow: INVITE,ACK,CANCEL,BYE,NOTIFY,REFER,OPTIONS,INFO,SUBSCRIBE. Content-Length: 0. . # U 2004/11/17 14:59:59.255737 68.80.201.101:5060 -> 216.229.127.60:5060 ACK sip:216.229.127.60:5060;lr SIP/2.0. Record-Route: sip:68.80.201.101;ftag=4edd147cdac0025f;lr=on. Via: SIP/2.0/UDP 68.80.201.101;branch=0. Via: SIP/2.0/UDP 192.168.0.83;rport=1063;received=68.80.200.100;branch=z9hG4bKe15e695c98bd9cb0. From: "Paul (1002)" sip:9990010001@sip.mycompany.com;user=phone;tag=4edd147cdac0025f. To: sip:14075551212@sip.mycompany.com;user=phone;tag=0bf5212d. Contact: sip:9990010001@68.80.200.100:1063;user=phone. Proxy-Authorization: DIGEST username="9990010001", realm="sip.mycompany.com", algorithm=MD5, uri="sip:4075551212@216.229.127.60:5060", nonce="419baee2139477c22db6d0ec9a47b23003512431", response="7b83435f78bc60f5ced80304c7d54093". Call-ID: aa31202374f54793@192.168.0.83. CSeq: 12010 ACK. User-Agent: Grandstream BT100 1.0.5.11. Max-Forwards: 16. Allow: INVITE,ACK,CANCEL,BYE,NOTIFY,REFER,OPTIONS,INFO,SUBSCRIBE. Content-Length: 0. . #
I guess, you are doing record-route for ACK also. IMO, you should not add record route headers for ACK.
I am not sure why Route header is completely removed from the request. Proxy is supposed to delete only the top route value.
-Ranga